Untwisted direct process yarn with even shrinkage



Patented July 25, 1933 near ears OSKAR G?PENLAENDER, 0F ELIVABETZ-ZTGN, AND RICHARD ELSSNER, OF JGI-INSON CITY,

TEIlNESSE-E, ASSIGNORS TO ABIEEICAN GLAITZSTOFI? CORPORATION, OF NEW YOREZ, N. Y., A CORPORATIQN 0F DELATVARE UNTWISTED DIRECT PROCESS YARN WITH EVE N SHRINKAGE N0 Drawing.

In the treatment of artificial silk, such as the process disclosed in copending application Serial Number 548,474 (applicants Bitter and Elssner), a procedure which may be followed in order to produce an even shrinkage of the ya n, is set forth. in application M8374, the filaments are covered with an As is well known,when filaments are dried in the ordinary manner, on perforated spools, the heated air is applied to both the surfaces, the outer layers immediately'dry, while the central layers are heated so that a very humid condition is produced there. This results in i the formation of an unyielding mass of moist or wet layers of thread which prevents the outer layers of the yarn body from shrinking. The inner layers, similarly, are pressing against the central portion of the spool which is likewise an unyielding surface and accordingly, dry without proper shrinkage. The

entral layers, however, do shrink. The resulting yarn body has a total uneven shrinkage which affects its physical properties and the manner in which it will take dyes.

in the present procesahowever, the yarn is directly collected, on extrusion, upon socalled collapsible spools. This term is to be construed to mean a spool, the surface of which is slotted, wherein wings or fins are caused to project through the slots during the winding of the filaments. These fins or wings cause the surface of the spool to be incremented in size during the time that the filaments are being wound thereon. When the winding is completed the fins or blades are allowed to retract, and the wound yarn body thereupon lies loosely upon the spool body per se.

In the present process, filaments are so wound, and then allowed to lie loosely on the body of the spool by decreasing the winding surface in the manner set forth. Aftertreat-.

ment of the filaments is necessary since they ing, a yarn with even upon the spool core, they Application filed July 2, 1932. Serial No. 820,?24.

must be deacidified, desulphurized, etc.

These steps take place on the spool, andwhile still wet, the outer surface of the spool is covered with an iinpermeable covering. The drying medium, for example, air, is then applied to the filaments from the inside only. Drying, accordingly, occurs from' one side only.

It may thus be seen that, in a single dryshrinkage may be produced. In the old method of drying from all sides at once, on rigid spools, as pointed out above, the outer and innermost filaments of the body do not have an opportunity to contract or shrink; In the present process, the innermost filaments dry first. Because they are in a relaxed state and areloosely lying are given an opportunity to shrink properly. The central portion and outermost portions,meanwhile,

As each successive are being slowly dried. layer of the filament body dries, it has ample opportunity to contract or shrink, and, therefore, when the outermost layers have finally dried, a yarn bodywith even shrinkage is produced.

It is not an object of the present invention to attempt to cover the construction of any collapsible spool, but what is claimed is:

1. In a process for treating artificial filaments,threads, etc., the steps of collecting them upon a spool or bobbin, retracting the winding surface so that the filaments etc. lie in a loose body upon the spool or bobbin, wet-treating the filaments, etc., covering the outer surface'thereof with animpermeable covering, and then drying the yarn body from the inside of the spool or bobbin only.

2. In a process ofproducing artificial filaments or yarn with an even shrinkage, the steps of winding the yarn on a spool the winding surface of which may be lessened in periphery, and, after reducing the saidsurface so that the yarn body lies loosely thereon, washing and drying the filaments, the drying step being accomplished by covering. the outer surface of the yarn body and drying from the inner side only. OSKAR OPP NLAENDER.

RICHARD ELSSNER. 

